Textile mill spindles



Au l 13, 1957 J. D. GLEITZ ETAL 2,802,330

TEXTILE MILL SPINDLES Filed April 2, 1954 INVENTORS Jf/PGME D. 42 5/ T2A. J. MOK/LTON United States Patent 6 TEXTILE MILL SPINDLES Jerome D.Gleitz, Pepper Pike Village, and Lloyd Jackson .Moulton, Mentor, Ohio,assignors, by mesne assignments, to Curtiss-Wright Corporation,Marquette Metal Products Division, Cleveland, Ohio, a corporation ofDelaware Application April 2, 1954, Serial No. 420,491

4 Claims. (Cl. 57-130) The invention relates. to an improved compositemetal blade and whorl unitof a textile mill spindle, consisting of asteel shaft for rotary support by a bolster, a barrel of light weightmetal, such as aluminum, properly configured to support a tube typebobbin, and a steel whorl for driving the spindle, all rigidly securedtogether as by press or shrink fitting methods on a common longitudinalaxis. The blade and whorl unit hereof is of a known specific type inwhich a tubular lower end portion of the (e. g.) aluminum barrel istightly held by and between a relatively rigid sleeve portion of thewhorl (called the acorn) and the shaft, which latter occupies an axialbore of the barrel and extends above the plane of the top end of theacorn for local reinforcement of the relatively weak aluminum and tocontrol flexure of the bobbin supporting portion generally of thespindle.

In the above outlined type of composite metal spindle, the parts must beconcentric within extremely narrow limits for the sake of proper dynamicbalance; the com ponents (at least the shaft and whorl) must bearpermanent precise axial relationships to each other; the necessarilyexposed joint between the whorl and the aluminum barrel must be tightlyclosed, presenting no fissures or rough or sharp surfaces such as caneither snag went the filament stockor yarn, as during placement anddofiing of bobbins, and the upper free end or bobbin supporting portionsof the spindle must strongly resist fiexure. Further the exposed surfaceportions next to the joint between the whorl and aluminum must, fordesirable operation, be defined by mutually flush smooth surfaces of thealuminum and the steel, and the aluminum adjacent the joint should beguarded by the steel from percussive contact by the bobbins which, attheir lower ends, usually have metal ferrules that are much harder thanthe aluminum. The general object of the present invention is to providea dynamically balanced spindle construction of the above outlined typecapable of being economically and precisely manufactured .in high quan-Y tity. Other objects will become apparent from the followingdescription of the preferred form of spindle as shown in theaccompanying drawing wherein:

Fig. 1 is a reduced scale assembly view, partly in central longitudinalsection, showing the present subject spindle with a tube type bobbinthereon (diagrammatically represented).

Fig. 2 is an enlarged scale, fragmentary sectional view showing portionsof the steel shaft, the partly finished aluminum barrel, and the partlyfinished steel whorl.

Fig. 3 is a view similar to Fig. 2 showing the sam parts fully finished.

Fig. 4 is a fragmentary View similar to Fig. 3 showing a modified formof joint between two components of the spindle.

Referring particularly to Fig. 1, the shaft I (assumed to be highquality uniformly hard steel) has a suitable circular surface 3 forengagement with the bolster bearing (not shown) and a precision finishedfootstep-engaging, generally conical, lower end portion 4. The steelwhorl ice 5 has the usual smooth circular surface 6 defined in part bythe usual flange formations 7 and 8, and has an integral acorn or sleeveportion 9. The aluminum barrel 10 (preferably forging quality aluminumalloy) is shown as tapered upwardly from a region close to the top ofthe whorl acorn to a bobbin supporting and driving tapered circular seat10a. the bobbin B rests firmly on the seat 10a and the lower hollow endof the bobbin loosely encircles the whorl acorn portion 9 around andbelow a bobbin-piloting surface portion 27 formed on the acorn near itstop end and which constitutes an annular ramp acting to guide the lowerend of the bobbin into approximately centered relation to the spindle asthe bobbin is placed on it. Seat 10a is of high wear resistance (e. g.may be a steel cap for'barrel 10).

In Fig. 2, showing the semi-finished whorl and barrel blanks 5x and 10xrespectively, and an upper portion 2 of the fully finished shaft 1within an axial bore 11 of the barrel blank, it can be noted that theacorn portion 9x of the whorl blank is of oversize diameter relative tothe finished contour of the acorn, the latter being indicated by brokenlines at 9. The oversize relationship of the barrel blank 10x, inrespect to the finished dimensions of the barrel 10, is similarly shownor indicated.

The barrel blank 10x is tightly taper fitted into the whorl blank 9x asby formation of smooth uniformly tapered mating surfaces 12, 12' onblank 10x and 13 on blank 9x. The degree of taper is any suitablelocking angle relative to the rotational axis of the spindle. Tapersurface portion 12' on the barrel blank extends upwardly into exposedposition beyond the top end or rim portion 9y of the whorl blank sleeveportion 9x. The upper and lower mating taper surface bearing areas areindicated 14 and 15, being defined, in part, by a generally reduceddiameter or relief formation 16 on the barrel blank, resulting in anannular clearance space 17 of considerble length when the members areforce fitted together. Thus the radial locking pressures which may beobtained with a given amount of axial assembly force are increased overwhat the pressures would have been in case full length complementarytaper fitting surfaces (same total length) had been used. Additionally,by provision of axially separated bearing areas, such as illustrated at14 and 15, the steel of the whorl Sand the aluminum of the barrel 10 canflex independently of each other as has been found effectual, when thecomponent metals have a marked difference in elasticity, in preventingaxial relative creeping movement of interference fitted telescopingmembers incident to application of strong flexing forces on theassembly.

Upper shaft portion 2 (for convenience stub portion) is in interferencefitted relationship to the axial receiving bore 11 of the barrel (blank10x) at axially spaced apart lower and upper bearing regions indicatedat 20 and 22, the axial spacing being achieved, in the illustratedarrangement, by a portion of a counterbore 23 surrounding a reduceddiameter upper end portion of the shaft (partially illustrated). Therelief around the shaft aiforded by counterbore 23 extends above andbelow the plane of the top of the acorn 9* of the finished spindle atwhich region the flexure resistance of the spindle changes more or lessabruptly. due to the relative rigidity of the steel whorl. When theshaft stub 2 is force fitted into bore 11 the upper relatively reduceddiameter portion of the shaft stub, which needs to be somewhat tight inthe bore at 22 in order properly to control flexure of the spindle,cannot cut metal from or otherwise deleteriously affect the metal of theportion of the barrel bore 11 which is designed to receive therelatively lower portion of the shaft stub, as at: interference fittingbearing region 20. 7

An internal upper surface of.

spindle so that the aluminum is continuously subjected tooutward andinward radial pressures by the steel parts during the operating life ofthe spindle. During assembly of the components described above (mannerof assembly given later) it is possible to secure a'tighter gripping ofthe extreme lower end portion of the aluminum barrel be tween the hardsteel shaft and the whorl (maximum stress region due to juxtaposition ofthe bolster bearing) than at any region thcreabove and without having toeffect any unusual or difficult maching operations on the parts such aswould lead to excessive cost.

Referring to the illustrated flush joint surface arrangements'Z'S and25a, as illustrated by Figs. 3 and 4 (two different forms), oneadvantage of the construction is that a butt type joint is avoided. Abutt type joint necessarily involves considerable reduction in diameterof the aluminum barrel Where it enters the whorl acorn (thus anespecially abrupt change in flexure resistance of the spindle at thejoint). Another advantage (over prior practice) is that the exposedmarginal surfaces adjacent the joint line (26 and 26a Figs. 3 and 4respectively) do not give rise to an outwardly exposed sharp or jaggedfeather edge around the top of the whorl acorn such as would occur if anattempt were to be made to eliminate an exposed upwardly facing annularshoulder at the top of the acorn by forming a bobbin-piloting generallyconical surface around the top of the acorn and which surface, in thecompleted assembly, extends into acute angular relationship to theperipheral external surface of the aluminum barrel all around thebarrel. A feather edge cannot be so formed on the acorn rim or topportion without sometimes presenting jagged surfaces which can cut theyarn or at least collect lint and the like.

Fig. 3 shows the result of machining away of the excess metal of theblanks 9x and 10x, which is done after complete assembly per Fig. 2,while the blanks are supported on the spindle axis (using bearingsurfaces 3 and 4, Fig. l, of the shaft 1 and a center socket 30 formedon the top end of the spindle in true axial alignment with the shaft, tomaintain concentricity of external spindle surfaces with said axis).Final finish is preferably effected by grinding. The bobbin guiding ramp27 around the whorl acorn, as shown in Fig. 3, is of curved contourupwardly to the joint line 26 where, as shown, it merges into (i. e. isflush with) a reverse curve 28 on the aluminum barrel 10. The bobbinpiloting or guiding ramp 27a, Fig. 4, is operatively similar to the ramp27 of Fig. 3 except that the major portion of ramp 27a is definitelyconical, the uppermost exposed flush joint surfaces, directly adjacentjoint line 26a, being formed as by an appropriately contoured grindingtool operating to cut across the interface surfaces of the aluminum andsteel at a greater angle with reference to the interface surfaces thanin the case of Fig. 3.

At the upper left of Fig. 3, a portion of'a conventional metal ferrule Bon the bobbin B is shown as though purposely moved to a pointapproximately as close as possible to the joint line 26; and it isevident that likelihood of the ferrule B (or any other portion of thebobbin) striking or defacing the aluminum exposed at curve surface 28adjacent the joint line 26, during loading of the spindle and indofling, is practically nonexistent. A typical mounted position of thebobbin on the spindle is partially illustrated at the right of Fig. 3.The ramp and joint defining surface relationships according to Fig. 4similarly protect the aluminum of the barrel 10 from being damaged bythe bobbin.

The preferred procedure in assemblying the parts (shaft 1, barrel blank10x and whorl blank x) is to support the shaft and whorl blank rigidlyagainst axial movement in a direction toward the footstep end 4 of theshaft and in their proper axial and concentric spaced apartrelationship, and then to force the barrel blank into place as by asingle operation of a press. In production, the shaft 1 is supported inthe press at the footstep end 4 of the shaft and laterally at itsbearing portion 3; and the inner axial shoulder 32 (Fig. 2) of cavity 31of the whorl blank 5x rests firmly on a suitable rigid support in thepress. Thus, even though metal parts which are joined, in high quantityproduction, by taper fitting are inherently subject to some axialvariation in relative position, the procedure hereof, as just described,assures maintenance of the whorls '5 and footstep ends 4 of the shaftsof various lots of spindles in precise uniform axial relationship; and,since the bobbin carrying surface portions of the barrel and whorl areformed later, any desired precision in axial relationships for bobbinsupport can be readily accomplished.

The center socket 30 in the top end of the barrel blank 10x (or its cappiece if it has one as mentioned earlier) is next formed on what will bethe true rotational axis of the spindle, as by supporting the assemblyin an appropriate chuck, vise or the like which engages only preciselyformed surfaces on the projecting portion of the shaft and thereby holdsthe shaft axis aligned with the center socket forming tool (not shown).Afterward the remaining operations necessary to finish the spindle aredone while the rigid assembly (1, 5x, 10x) is held on center through theshaft and socket in accordance with common machining practice.

The above described taper fitting of the steel whorl around the lowerend portion ofthe aluminum barrel (aside from specific features alreadydescribed) has several distinctive operating advantages over taperfitting of a steel shaft into a mating socket in an aluminum barrel asalready known in the art. By way of summary, or partly so, one advantageis that the subject construction enables very accurate axialrelationships to be maintained in quantity production between the shaftand whorl.

despite the well known inherent limitations of taper fitted metal parts.In the case of employing a taper fit between the shaft and barrel, evenwhen the shaft stub to be inserted into the barrel is made large indiameter, the diameters of the interfitted parts are small in comparisonwith those involved in taper fitting of the whorl to the barrel, hencelikelihood of variation in axial relationships in the latter case is ofa different order, being decreased by larger surface contact per inch oflength in contact.

A further important advantage is involved with the fact alreadyoutlined, namely that when the spindle is mounted in its bolster and theupper end of the spindle is subjected to strong lateral force, thehighest internal stresses will occur at the base portion of thecomposite structure, i. e. just above the bolster bearing. Assuming allthe mating surfaces of the blanks or parts as herein shown and describedare fully finished prior to assembly, then, when the shaft stub 2 isinserted into its receiving bore 11 of the barrel blank 10x, therelatively small diameter and relatively thin walled lower end portionof the relatively soft barrel blank is always slightly expanded radiallyoutwardly to some extent. Thus when the mating taper surfaces 12, 12',13 are finally forced together, greater radial'pressures will be exertedbetween the surfaces which form the lower bearing region 15 than betweenthe surfaces forming the upper bearing region 14. concomitantly theshaft 1 in the plane of the bearing region 15 will be somewhat morefirmly gripped by the adjacent aluminum surface than it was as a resultof its own press fitting into the barrel bore. Thus the above justdescribed advantage largely offsets the tendency of press fitting ofsteel into aluminum to produce a weak joint when, inter alia, largetolerances are used.

Still another advantage of the present construction is that it lendsitself economically to shrink fitting of the tapered surfacestogetherwithout having to subjectthe aluminum to abnormally hightemperatures or the parts to be so fitted together to a high temperaturedifference. The shaft 1 and its receiving bore are necessarily of smalldiameter, for which reason it would be costly to obtain the necessarytemperature difference such as would enable shrink fitting of the shaftinto the barrel; and if the aluminum is heated above criticaltemperatures in the operation its strength is impaired. On the otherhand the surfaces involved in shrink fitting of the whorl 5 onto thebarrel are of relatively large diameter and the steel of which the whorlis always made can safely be heated to appropriate above-normaltemperatures for obtaining an operatingly permanent adequately tightinterference fitting of the parts.

We claim:

1. A composite metal, textile mill spindle blade and whorl unit,comprising a one piece hard steel shaft having a footstep end portionand a bolstenbearing-engaging circular surface between its ends, abarrel of light weight metal exteriorly formed to support a bobbin andhaving a bottom axial bore in interference fitted gripping contact witha portion of the shaft lying above its bolsterbearing-engaging surface,and a substantially rigid steel whorl telescoping the barrel and ininterference fitted gripping contact with a lower end portion of thebarrel, characterized in that the mating surfaces of the shaft and itsreceiving bore in the barrel are principally cylindrical, and the matingsurfaces of the barrel and whorl are principally tapered and ofdecreasing diameter toward the footstep end of the spindle, furthercharacterized in that the tapered mating surface contact of the whorland barrel comprise two bearing regions of tapered surface contact, oneadjacent the bottom of the barrel and one adjacent the top of the whorl,said regions being axially separated by a clearance region all aroundthe barrel and defined by radially separated peripheral surfaces of thebarrel and whorl.

2,. The spindle construction according to claim 1 wherein the matinginterference fitting surfaces of the shaft and barrel bore compriseregions of bearing contact radially opposite both said axially separatedtaper bearing regions and another separate region of bearing contactbetween the shaft and barrel bore upwardly from the top of the whorl anddefined in part by a clearance space all around the shaft between it andthe barrel bore which clearance space extends above the top of thewhorl.

3. A composite, metal, textile mill spindle blade and whorl unitcomprising a central steel shaft adapted to be supported for rotation ina bolster, a light weight metal barrel of circular cross section adaptedto support a bobbin and having an axial bore in permanent tight grippingcontact with an upper end portion of the shaft, and a steel whorltelescoping the barrel and in interference taper fitting contacttherewith at the lower end portion of the barrel, further characterizedby provision of a closed joint at the circular interface surfaces of thebarrel and whorl around the upper end of the whorl, the defining exposedsurfaces of the joint being flush with each other, sloped outwardly anddownwardly and intersecting the upward terminal portions of theinterface surfaces at an acute angle relative to the rotational axis ofthe spindle unit all around the unit.

4. The construction according to claim 3, wherein the surfaces of thebarrel and whorl adjacent the line formed by the interface surfacesabout the unit are relatively reverse curves the lower of which, on thewhorl, forms a radially outwardly and downwardly sloping annularshoulder all around the unit to serve as a bobbin pilot when the bobbinis placed on the unit.

References Cited in the file of this patent UNITED STATES PATENTS264,297 Iaquith Sept. 12, 1882 651,702 Draper June 12, 1900 1,061,266Chapman May 13, 1913 2,463,484 Gelpke Mar. 1, 1949 2,536,618 Wood Jan.2, 1951 2,609,254 Harris Sept. 2, 1952

